Textile fabrics, in particular those which are used as an insert for the manufacture of coated materials, must meet a wide range of requirements. Examples of the use of such inserts are, among other things, textile backings for fitted carpets, textile reinforcements in PVC flooring or roofing sheets.
When used in the manufacture of roofing sheets, the inserts or reinforcing inserts used must have sufficient mechanical stability, such as good perforation strength and good tensile strength, which are brought about, for example, upon further processing, such as bituminization or laying. In addition, a high resistance to thermal stress, for example in the case of bituminizing or against radiant heat, and resistance to flying sparks is required.
When used in the manufacture of coated flooring, for example PVC flooring, additional demands are placed on such inserts. In this field of application, in addition to the mechanical/thermal requirements, the inserts must also avoid the formation of gaseous substances, since otherwise, blistering would be observed during manufacture, for example by the formation of water vapor. Blistering of this kind is highly problematic and leads to losses in yield or to poorer quality.
Additional requirements are placed on such inserts for use in the manufacture of surfaces in the interior and exterior of buildings. In this field of application, in addition to the mechanical/thermal requirements, the inserts must also have decorative properties which remain unchanged or almost unchanged over a long period of time.
In addition to the aforementioned technical requirements, environmental compatibility or new legal regulations are also responsible for the replacement of existing, occasionally properly functioning systems with new, compliant systems. Examples in this regard include new industrial standards, such as DIN EN 14041, or legislative changes, such as REACH.
The binding systems used hitherto for consolidating textile surfaces are based on thermoplastic and/or thermoset binder systems. Examples which may be mentioned here are aminoplasts and binders based on acrylates.
EP-A-2192153 discloses binder systems based on crosslinked polycarboxylates and starch. EP-A-2987827 describes binder systems based on polyacrylates, wherein these are not crosslinked by means of a low molecular weight crosslinker, and starch. Further binder systems based on polyvinyl acetate and starch are known from EP-A-2607533. The binder systems described are already very well suited for the manufacture and consolidation of textile fabrics and have good heat resistance. For some applications, however, the wet strength and color stability should be improved. Furthermore, a reduction in binder costs is an important goal of binder development. In addition, the ever-increasing demand for binder systems which are predominantly based on renewable raw materials has to be met.
There is thus a considerable need for the provision of novel binder systems for consolidating textile surfaces which are intended to be used as inserts, which on the one hand satisfy the technical requirements and the legal provisions, and on the other hand are economically accessible. In addition, novel binder systems should be able to be used in existing production systems and applied by means of known methods and equipment. The novel binder systems should predominantly be based on renewable raw materials.